[Therion] Can't open data.log file for input

I’m running Therion v 5.3.11 on a Mac. I’ve just reinstalled Mavericks to fix a problem and now get the following error. Anyone know what the problem is? ####################### metapost log file ######################## therion: warning -- can't open data.log file for input can't open data.log file for input#################### end of metapost log file #################### therion: error -- metapost exit code -- 32512 writing xtherion file ... done Dave Clucas dave.clucas@icloud.com